summaryrefslogtreecommitdiffstats
path: root/src/corelib/global/qendian.qdoc
blob: 9ce9dbdb0e534f690043f3fbd5ac8060db126054 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
** $QT_END_LICENSE$
**
****************************************************************************/

/*!
    \headerfile <QtEndian>
    \title Endian Conversion Functions
    \ingroup funclists
    \brief The <QtEndian> header provides functions to convert between
    little and big endian representations of numbers.
*/

/*!
    \internal
    \fn T qFromUnaligned(const void *ptr)
    \since 5.5

    Loads a \c{T} from address \a ptr, which may be misaligned.

    Use of this function avoids the undefined behavior that the C++ standard
    otherwise attributes to unaligned loads.
*/

/*!
    \internal
    \fn void qToUnaligned(T t, void *ptr)
    \since 4.5

    Stores \a t to address \a ptr, which may be misaligned.

    Use of this function avoids the undefined behavior that the C++ standard
    otherwise attributes to unaligned stores.
*/


/*!
    \fn T qFromBigEndian(const void *src)
    \since 4.3
    \relates <QtEndian>

    Reads a big-endian number from memory location \a src and returns the number in the
    host byte order representation.
    On CPU architectures where the host byte order is little-endian (such as x86) this
    will swap the byte order; otherwise it will just read from \a src.

    \note Template type \c{T} can either be a qint16, qint32 or qint64. Other types of
    integers, e.g., qlong, are not applicable.

    \note Since Qt 5.7, the type of the \a src parameter is a void pointer.

    There are no data alignment constraints for \a src.

    \sa qFromLittleEndian()
    \sa qToBigEndian()
    \sa qToLittleEndian()
*/
/*!
    \fn T qFromBigEndian(T src)
    \since 4.3
    \relates <QtEndian>
    \overload

    Converts \a src from big-endian byte order and returns the number in host byte order
    representation of that number.
    On CPU architectures where the host byte order is little-endian (such as x86) this
    will return \a src with the byte order swapped; otherwise it will return \a src
    unmodified.
*/
/*!
    \fn T qFromLittleEndian(const void *src)
    \since 4.3
    \relates <QtEndian>

    Reads a little-endian number from memory location \a src and returns the number in
    the host byte order representation.
    On CPU architectures where the host byte order is big-endian (such as PowerPC) this
    will swap the byte order; otherwise it will just read from \a src.

    \note Template type \c{T} can either be a qint16, qint32 or qint64. Other types of
    integers, e.g., qlong, are not applicable.

    \note Since Qt 5.7, the type of the \a src parameter is a void pointer.

    There are no data alignment constraints for \a src.

    \sa qFromBigEndian()
    \sa qToBigEndian()
    \sa qToLittleEndian()
*/
/*!
    \fn T qFromLittleEndian(T src)
    \since 4.3
    \relates <QtEndian>
    \overload

    Converts \a src from little-endian byte order and returns the number in host byte
    order representation of that number.
    On CPU architectures where the host byte order is big-endian (such as PowerPC) this
    will return \a src with the byte order swapped; otherwise it will return \a src
    unmodified.
*/
/*!
    \fn void qToBigEndian(T src, void *dest)
    \since 4.3
    \relates <QtEndian>

    Writes the number \a src with template type \c{T} to the memory location at \a dest
    in big-endian byte order.

    Note that template type \c{T} can only be an integer data type (signed or unsigned).

    There are no data alignment constraints for \a dest.

    \note Since Qt 5.7, the type of the \a dest parameter is a void pointer.

    \sa qFromBigEndian()
    \sa qFromLittleEndian()
    \sa qToLittleEndian()
*/
/*!
    \fn T qToBigEndian(T src)
    \since 4.3
    \relates <QtEndian>
    \overload

    Converts \a src from host byte order and returns the number in big-endian byte order
    representation of that number.
    On CPU architectures where the host byte order is little-endian (such as x86) this
    will return \a src with the byte order swapped; otherwise it will return \a src
    unmodified.
*/
/*!
    \fn void qToLittleEndian(T src, void *dest)
    \since 4.3
    \relates <QtEndian>

    Writes the number \a src with template type \c{T} to the memory location at \a dest
    in little-endian byte order.

    Note that template type \c{T} can only be an integer data type (signed or unsigned).

    There are no data alignment constraints for \a dest.

    \note Since Qt 5.7, the type of the \a dest parameter is a void pointer.

    \sa qFromBigEndian()
    \sa qFromLittleEndian()
    \sa qToBigEndian()
*/
/*!
    \fn T qToLittleEndian(T src)
    \since 4.3
    \relates <QtEndian>
    \overload

    Converts \a src from host byte order and returns the number in little-endian byte
    order representation of that number.
    On CPU architectures where the host byte order is big-endian (such as PowerPC) this
    will return \a src with the byte order swapped; otherwise it will return \a src
    unmodified.
*/